Heat exchanger



Oct. 7, 1969 M. MENKUS 3,470,950

' HEAT EXCHANGER Filed Jan. '31, 1967 Sheet-Sheet 2 INVENTOR.

- MILTON MENKUS A T TO R N E Y.

Oct. 7, 1 9 69 M. MENKUS 3,470,950

Filed Jan. 31, 1967 5 Sheets-Sheet 3 F I G 4.

I 4 V EN T ()R.

MILTON M E N K US BY g g I A T T O R N E Y.

Oct. 7, 1969 M. MENKL JS 3,470,950

HEAT EX C H AN G E H Filed Jan. '31, 1967 5 Sheets-Sheet 4 I N V E N 7 OR.

MILTON M E N K US BY g g A T T O R N E Y.

Oct; 7, 1969 MENKU$ 3,470,950

HEAT EXCHANGER Filed Jan. 31, 1967 5 Sheets-Sheet 5- I V E TOR MILTON M E N K US ATTORNEY.

United States Patent 3,470,950 HEAT EXCHANGER Milton Menkus, 22 Maplewood Terrace, Springfield, Mass. 01108 Filed Jan. 31,1967, Ser. No. 612,927 Int. Cl. F28rl 7/02 US. Cl. 165-165 Claims ABSTRACT OF THE DISCLOSURE A labyrinth-type heat exchanger having a plurality of separators or barriers arranged to define a plurality of cells or chambers disposed in a checkerboard fashion, portions of certain of the separators bounding the chambers being upset or deformed, or in some cases removed, so as to allow intercommunication between adjacent chambers thereby to define tortuous spirally-wound or helical screw type flow courses or paths through the chambers, with adjacent flow courses or paths and the separators therebetween constituting the heat exchanger.

BACKGROUND OF THE INVENTION Field of the invention The invention relates to a labyrinth-type heat exchanger for effecting transfer of heat from a fluid or fluids flowing at one side of a barrier to another fluid or fluids flowing on the other side of the barrier, which heat exchanger has as many applications as there are uses for heat exchangers generally. For example, it may serve as a boiler, or an appendage to a boiler, or as a furnace, or as a roof, wall or structural panel of a building or room or the like with inherent ducting and heat exchange, or as a separate accessory where outside air used for make-up in a building may be heated by air being exhausted from that building. It may serve as a wall or structural panel of a building as aforesaid, its unique characteristics offering great rigidity as well as heat exchange potential. Further, it may be exploited by its use for accoustical treatments inherent in its design as a labyrinth-type heat exchanger, same lending themselves inherently to instances where noise is a serious problem in connection with air or other fluid handling.

The system requires acceleration and deceleration of fluid flow due to variations in the area available in the course of intercellular flow as fluid is progressed through a flow path. Too, pulsing type velocity changes in fluid flow will occur, same resulting in expansion or contraction, causing the labyrinth or helical flow to accelerate and decelerate and to change paths whereby turbulence is increased to enhance heat transfer.

Description of the prior art Efficient heat exchangers of the prior art have been expensive in manufacture, complicated in design, lacking in flexibility as to fields of use, and limited as to scope of application.

The need for an efficient heat exchanger of simple design having a high rate of heat transfer together with a facility, by virtue of a manifolding feature, to provide a wide range of capacities, has long been felt.

SUMMARY OF THE INVENTION A primary object of the invention is to provide a heat exchanger of modular type design wherewith infinite variations can be approached by the simple expedient of increasing or decreasing the number of modules, or the size of the modules, or the length of configuration of the flow paths.

Another object is to provide a heat exchanger for fluids having an extremely high rate of heat transfer resultant from the unique construction of the fluid flow paths through the structure, which structure has an extremely high strength in its design.

As another feature worthy of particular notice, the exchanger hereof may be used as either a parallel or counterflow type or as a temperature equalizer prior to fluid blending.

In one of its embodiments, the exchanger may be arranged in a plurality of planar groups, in manner such that a flow path of one group may be enclosed on all of its planes by other flow paths of its own group or of adjacent groups.

It olfers the advantages of being structurally sound and economically produced so as to allow ready removal and replacement to the almost complete elimination of main tenance costs, all based upon the principle of planned replacement.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a fragmentary, partially exploded view in perspective of a grille or grid of the type from which the heat transfer element may be formed;

FIG. 2 is a fragmentary, partially exploded view, in perspective, of one form of heat transfer element of a heat exchanger of the invention;

FIG. 3 is a fragmentary view, in perspective, of a heat exchanger embodying a form of the invention wherein the fluid flow paths of the heat transfer element are vertically disposed;

FIG. 4 is a fragmentary view, in perspective, of a heat exchanger embodying a form of the invention wherein the fluid flow paths of the heat transfer element are diagonally disposed;

FIG. is a fragmentary view, in perspective, of a heat exchanger embodying another form of the invention wherein a plurality of heat transfer elements are arranged in a stacked relationship; and

FIG. 6 is a fragmentary view, in perspective, of another form of heat transfer element wherein the fluid flow paths thereof are vertically disposed.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Heat exchangers may take the form of one or two or more heat transfer elements enclosed and/or separated by heat transfer walls or plates and connected, as by suitable inlet headers or inlet lines, to supply sources of heated and/or cooled fluids and further being provided with suitable outlet headers or outlet lines. Such headering means for inlet and outlet purposes, being widely variable with respect to type, have not been illustrated in the drawings, in order to simplify same and to restrict the disclosure to the heart of the invention.

Herefollowing, where the term fluid is employed, it will be understood to mean anything that will flow, whether of liquid or gaseous form.

The invention has been labeled a heat exchanger for purposes of convenience, the term being used in its classical sense of any device used to transfer heat from a fluid flowing on one side of a barrier to another fluid flowing on the other side of the barrier.

With detailed reference now to the drawings, FIG. 1 illustrates a grille or grid or latticework formed of metal, plastic, or equivalent material and being of the type from which heat transfer elements embodying the invention are preferentially, but not obligatorily, fabricated. Same comprises a plurality of equi-spaced, parallel, upright longitudinally-extending bar-like walls 20 and a plurality of equi-spaced, parallel, upright, transversely-extending barlike walls 30 normal to and intersecting walls 20 thereby to define a plurality of generally square or rectangular or other shape, noncommunicating, cells or chambers 40, each such cell or chamber being bounded by portions of a pair of adjacent walls and portions of a pair of adjacent walls 30.

Such grille or grid or latticework so described may be of the interdigitating type as frequently employed in fluorescent light fixtures for diffusion of light.

FIG. 2 illustrates a heat transfer element 10, embodying one form of the invention, and formed by upsetting or deforming certain portions of certain of walls 20 and intermediate adjacent chambers to afford communication between said chambers. A plurality of such communicating chambers define a flow path.

Certain of walls 20 and 30 are upset or deformed, not randomly, but according to a pattern or patterns, so as to provide a plurality of flow paths through the heat transfer element, as will be explained more fully hereinafter.

Portions of walls 20 and 30 are deformed downwardly from their respective top planar surfaces or are upset upwardly from their respective bottom planar surfaces so as to project normally in the direction of fluid flow and t; allow ports communicating between adjacent chamers.

Such upsetting or deforming may be at either side of a particular wall 20 or 30. For example, in FIG. 2, a wall 20 is shown as provided with a plurality of equi-spaced tabs 22 which are formed by deforming or bending the wall downwardly from its top planar edge so that the tabs may extend outwardly from each side face of the wall in an alternating manner and thereby define a plurality of equi-spaced ports 24 through the wall.

A wall 30 is shown as provided with a plurality of equi-spaced tabs 32 formed by upsetting or bending the wall upwardly from its bottom planar edge so that the tabs may extend outwardly from each side face of the wall in an alternating manner and provide a plurality of equi-spaced ports 34 through the wall.

Such system of upsetting certain portions of walls 30 either inwardly or outwardly or of deforming certain portions of the Walls 20 either inwardly or outwardly, all whereby intercommunication between certain of the cells or chambers 40 is obtained, is carried out throughout the entirety of heat exchange element 10, so as to provide a plurality of fluid flow paths therethrough.

Ports 24 and 34 afford communication between adjacent cells or chambers 40, with the fluid flow being in an up-and-down, zig-zag, tortuous path, as will be more fully explained hereinafter.

The flow paths thus provided offer the advantage of obtaining greater turbulence of the fluid or fluids passed therealong.

In FIG. 3 is illustrated a form of heat exchanger comprising a heat transfer element or core 10 sandwiched between inboard and outboard heat transfer walls or plates and 52 respectively and further enclosed by side walls or plates 54.

Suitable headers, not shown, for serving the usual header functions, will be strategically connected to the heat transfer element to provide fluid inlets to and outlets from the heat exchanger.

In the FIG. 3 embodiment, vertical fluid flow paths are shown, which flow paths are, for the sake of convenience only, referred to as heated and cooled fluid paths since they could be reversed.

The heated fluid paths are indicated by the arrows A and the cooled fluid paths are indicated by the arrows B, with shading being applied only to the heated fluid path for purposes of clarity. The paths can be of the parallel or counterflow type, as desired, counterflow being herein illustrated.

Paths A and B alternate throughout the width of the heat exchanger, with the flow being through a port 34, under a tab 32, into one chamber 40, through a port 24, over a tab 22 and into the next adjacent cell or chamber 40 disposed immediately thereabove or therebelow, where the process is repeated.

It is to be noted that when the flow paths are of equal lengths equal pressure drops are maintained from the inlet header to the outlet header, thereby avoiding short circuiting paths which tend to reduce the overall efliciency of heat transfer.

Differing flow path lengths may be utilized in those instances where it might be advantageous to do so, as in a triple, quadruple or larger fluid heat exchange system.

Each flow path pattern occurs in a zig-zag or checkerboard fashion, with each cell or chamber having a tab in the third direction which is mutually perpendicular to the planes formed by the walls and parallel with the plates.

The FIG. 4 embodiment is identical in construction to that shown in FIG. 3, except that diagonal hot and cold flow paths C and D respectively are shown in lieu of vertical flow paths.

It will be appreciated that vertical and/or horizontal flow paths or combinations of diagonal, vertical and horizontal flow paths may be employed.

In the FIG. 5 embodiment, I have shown a manifold or sandwich construction comprising an intermediate heat transfer element disposed between an upper heat transfer element 210 and a lower heat transfer element 310, upper heat transfer element 210 being enclosed by a pair of lower and upper heat transfer walls or plates 250 and 252 respectively, and lower heat transfer element 310 being enclosed by a pair of lower and upper heat transfer walls or plates 350 and 352 respectively.

The heat transfer elements are stacked in seriatim with central heat transfer element 110 being enclosed by lower plate 250 of upper heat transfer element 210 and by upper plate 352 of lower heat transfer element 310.

The heat transfer elements are also enclosed by side walls or plates, not shown, and the ends will be suitably connected to headers, also not shown, for fluid inlets and outlets.

While only three heat transfer elements have been shown in the drawing, I do not desire to be limited thereto since any number of elements of any desired flow path length or arrangement may be employed to meet different installation or heat transfer requirements.

Each heat transfer element is comprised of spaced, parallel longitudinally-extending bar-like walls intersected by spaced, parallel, transversely extending bar-like walls as with the FIGS. 14 embodiment.

By stacking the heat transfer elements, greater capacity of fluid flow and more complete and eflicient heat transfer may be obtained. For example, flow path E of central element 110 is bounded on two sides in its own plane by flow paths F and G, is bounded on its upper side in the next upper horizontal plane by flow path H, and is bounded on its lower side in the next lower horizontal plane by flow path I.

Of course, the relationship between the flow paths in the several planes may be varied. That is, a hot flow path in the central element may be bounded on its upper and lower sides by hot paths or by cold paths or it may be bounded on all of its sides by a counter flow path.

In the embodiment shown in FIG. 6 the tabs have been omitted, whereby the heat transfer element is particularly adapted for fabrication from a suitable plastic material, as by a molding process.

The tabless, plastic element is preferable for use in those instances where strength and rigidity are not critical factors and especially when the element may be periodically removed, discarded and replaced rather than cleaned in a program of planned replacement.

Herein, a plurality of equi-spaced, parallel and upright walls 420 of a heat transfer element 410 are intersected by a plurality of equi-spaced, parallel and upright walls 430 to define a plurality of cells or chambers 440.

The walls 420 are provided along their top edges with a plurality of spaced ports 424 and the walls 430 are provided along their bottom edges with a plurality of spaced ports 434, the ports 424 and 434 opening into the cells or chambers 440.

The fluid flow paths may be either vertical, horizontal or diagonal as with the FIGS. 25 embodiments.

In FIG. 6, the flow paths K, L and M are vertical.

While the cells or chambers in all of the embodiments have been shown to be of square or rectangular form, it is to be understood that they may be hexagonal or other form.

The axis of a flow path need not necessarily be linear and can comprise any combination of part linear and part zig-zag, not only in one plane or dimension but in two or three planes or dimensions.

I claim:

1. In a heat exchanger for imparting the heat of one fluid to another fluid without commingling the fluids by passing the fluids through sinuous passages within a common structure, the improvement consisting of a grille (a) comprising a plurality of longitudinally-extending walls intersected by a plurality of transversely-extending walls defining a plurality of cells,

(b) opposite cell-enclosing walls each mutually perpendicular to both the longitudinally and transversely extending walls,

(c) certain portions of certain of the longitudinally and transversely-extending walls being deformed at their top edges and certain portions thereof being deformed at their bottom edges for defining ports,

(d) the cell-enclosing walls and certain of the deformed portions and certain of the non-deformed portions of certain of the longitudinally and transversely-extending walls cooperantly defining first (1) a multiplicity of spaced primary series of intercommunicating fluid-carrying cells disposed in a common plane, each of the primary series defining a tortuous first fluid-flow path,

and second (2) a multiplicity of spaced secondary series of intercornmunicating fluid-carrying cells disposed in the same common plane, each of the secondary series defining a tortuous second fluidflow path,

(e) each of the secondary series being contiguously juxtaposed between an adjacent pair of primary series;

and means permitting inflow and outflow of fluids relative to the grille.

2. In the heat exchanger as set forth in claim 1, the flow paths of the multiplicity of primary series of fluid-carrying cells extending in a common direction and the flow paths of the multiplicity of secondary series of fluid-carrying cells extending in a direction opposite to said common direction.

3. In the heat exchanger as set forth in claim 1, the flow paths of the multiplicity of primary series of fluidcarrying cells and the multiplicity of secondary series of fluid-carrying cells extending in the same direction.

4. In a heat exchanger according to claim 1, the porting between the fluid-carrying cells of :a primary series providing an undulating zig-zag modified helical fluid path.

In a heat exchanger according to claim 1, the porting being formed by deforming certain portions of certain walls from one edge and by deforming certain other portions of certain other walls from the opposite edge.

6. In a labyrinth-type heat exchanger for imparting the heat of one fluid to another fluid without commingling of the fluids by passing the fluids though sinuous passages within a common structure, the improvement consisting of a plurality of grilles disposed in stacked relationship in a multiplicity of planes,

(a) each grille comprising a plurality of longitudinallyextending walls intersected by a plurality of transversely-extending walls defining a plurality of cells,

(b) a cell-enclosing wall disposed between and common to pairs of adjacent grilles of the stack and a cell-enclosing wall disposed on the opposite outer sides of the stack, each cell-enclosing wall being mutually perpendicular to the longitudinally and transversely extending walls,

(c) certain portions of certain of the longitudinally and transversely-extending walls being deformed at their top edges and certain portions thereof being deformed at their bottom edges for defining ports,

(d) the cell-enclosing walls and certain of the deformed portions and certain of the non-deformed portions of certain of the longitudinally and transversely-extending walls cooperantly defining first (1 a multiplicity of spaced primary series of intercommunicating fluid-carrying cells disposed in a common plane, each of the primary series defining a helical screw-type first fluid-flow course, and second (2) a multiplicity of spaced secondary series of intercommunicating fluid-carrying cells disposed in the same common plane, each of the secondary series defining a helical screw-type second fluid-flow course,

(e) each of the secondary series being contiguously juxtaposed between an adjacent pair of primary series,

(f) and each of the secondary series of each intermediate grille being juxtaposed adjacent a primary series on each of its sides; and

means for permitting inflow and outflow of the fluid relative to the grilles.

7. In the heat exchanger as set forth in claim 6, the fluid-flow courses of the multiplicity of primary series of fluid-carrying cells extending in a common direction of and the fluid-flow courses of the multiplicity of secondary series of fluid-carrying cells extending in a direction opposite to the common direction.

In the heat exchanger as set forth in claim 6, the fluid-flow courses of the multiplicity of primary series of fluid-carrying cells and the multiplicity of secondary series of fluid-carrying cells extending in the same direction.

9. In a heat exchanger according to claim 6, the porting between the fluid-carrying cells of a primary series providing an undulating zig-zag modified helical fluidflow course.

10. In a heat exchanger according to claim 6, the porting being formed by deforming certain portions of certain walls from one edge and by deforming certain other portions of certain other walls from the opposite edges.

References Cited UNITED STATES PATENTS 3,016,921 1/1962 'Iadewald 166 X 3,225,824 12/1965 Wartenberg 165--166 X FOREIGN PATENTS 215,482 5/1924 Great Britain.

ROBERT A. OLEARY, Primary Examiner T. W. STREULE, Assistant Examiner 

